Stereolithography apparatus comprising a cartridge device

ABSTRACT

In a stereolithography device ( 1 ), a three-dimensional object ( 2 ) is generated by curing a photosensitive substance ( 3 ) under the action of specific radiation, wherein the device includes a support unit, a radiation source ( 8 ) for generating the radiation, and a cartridge unit ( 10 ) that can be positioned on the support unit and removed therefrom. The cartridge unit ( 10 ) includes an interior space ( 140 ) surrounded by a casing ( 14 ), wherein the casing of the cartridge unit is deformable and at least partially transparent to the radiation triggering the curing process. The interior space ( 140 ) surrounded by the casing has a volume including a receiving space ( 4 ) in which the photosensitive substance ( 3 ) is present for at least a duration of an irradiation and curing process and accessible to the radiation.

The invention relates to a stereolithography device for producing athree-dimensional object by way of layered or continuous curing of aphotosensitive substance under the action of specific radiationtriggering the curing process, the device comprising:

-   -   a support unit;    -   a radiation source for generating the radiation triggering the        curing process; and    -   a cartridge unit that can be positioned on the support unit and        removed therefrom.

Devices of this type are well-known. A stereolithography apparatus isused to create a three-dimensional body from a photosensitive substanceby bonding layers or layer information in a layer by layer fashion orcontinuously. The invention is directed to the use of an improvedcartridge system, which can be used in such an apparatus and surroundsthe object to be produced.

The term stereolithography denotes a production process in which alight-sensitive substance that solidifies upon irradiation with light,and which in general is a liquid monomer formulation, is used togenerate a three-dimensional body (“object”) having a predefinabledesired shape in a layer by layer fashion by generating geometric layerinformation, which can be generated, for example, by way of a digitalmask or by a moving laser beam. The fundamental principle ofstereolithography is also known by terms such as rapid prototyping, 3Dprinting and the like.

In addition to a controllable laser, pixel-based display units,incoherent light sources, for example in conjunction with controllablemicromirrors (known as MEMS or DLP chips), may be used for thestereolithography process for projecting geometric layer informationinto a photosensitive substance, so as to cure (“develop”) thissubstance in a layer by layer fashion or continuously on the bottom oranother defined reference surface. The layer information may, inparticular, be pixel-based. The reference surface (also referred to asreference plane) represents a defined surface area on which the curingof a layer of the photosensitive substance takes place; this may be thesurface of the inside of the bottom or lid or another suitably definedsurface area and, depending on the application, may have a suitablesolid, flexible or liquid consistency. So as to separate the cured layerfrom the reference surface, this layer is first, which is to say priorto the first step of the generative process, transferred onto a support(for example, attached by way of a polymerization process), which isable to carry out a relative movement with respect to the focal plane,which may coincide with the upper face of the reference surface (forexample the cartridge bottom). A next method step ensures that newmaterial of the photosensitive substance is able to subsequently flowbetween the most recently generated layer and the reference surface;this may take place by way of a simple stroke movement, for example. Thesubsequent flow of photosensitive substance can then, in turn, be curedby way of exposure. These method steps are repeated until the object tobe formed has been built according to the individual projected pieces oflayer information.

The greatest problems of these methods lie primarily in the effectiveand variable storage or safekeeping of the photosensitive substancewithin the apparatus itself, as well as in the gentle separation of theindividual layers from the reference surface, the effective control ofthe relative movement of the support of the generated layers or of thegenerated object with respect to the reference surface, and in handlingof the apparatus and feeding of new photosensitive material into theapparatus in a manner that is as simple as possible.

A variety of approaches are described in the prior art, which usuallyprovide open vat-shaped receptacles for the photosensitive substance. Inaddition, cartridges have been described; however, these represent verycomplex, rigid and cumbersome receptacles.

DE 10 2014 215 213 A1, for example, describes a receptacle in which afilm joined to a bottom plate is provided, which is stretched downwardlyby a non-transparent portion. This film may be deformed when the layersare lifted off so as to enable easier and gentler detachment. Thereceptacle is an assembled, complex assembly, which comprises, amongother things, the bottom plate, a tensioning part protruding into thereceptacle, and various other parts, such as the support itself, and hasa complicated design.

Other approaches, such as in DE 101 19 817 A1 and JP H06 246 838 A, usean open, vat-shaped geometry instead of a closed cartridge, and likewiseinclude a deformable film so as to reduce the peel-off forces.

The known approaches have the disadvantage that the design of thecartridge system and of the vats themselves is very complex, andfurthermore have disadvantages regarding the handling of thephotosensitive substance, such as cleaning the vat, inserting the vat inthe apparatus, establishing a precise amount to be added, as well as theexposed liquid level in the case of vat systems, the hazard of makingdirect contact with the photosensitive substance and/or of contaminatingthe apparatus itself during replenishment or transfer. Considerabledisadvantages also arise during the insertion of a vat filled withphotosensitive material and/or during removal of the vat sincecomplicated clamping mechanisms have to be actuated, or the vat has tobe pushed into holding devices. The problem of contaminating theapparatus and/or the operator, in particular of contaminating individualapparatus components or component groups, also exists during the removalof the generated component, requiring cleaning when switching to adifferent photosensitive material, which is a cumbersome andtime-consuming process. Another disadvantage is that conventionalapproaches do not allow the apparatus to be operated under a certainatmosphere or certain atmospheric conditions. Cleaning the generatedobject also represents a problem since, during the removal of thesupport of the object from the apparatus, uncured monomers wetting theobject can contaminate the apparatus as well as the installation site ofthe apparatus, in addition to a possible contamination of the user. Dueto the exposed liquid level, the photosensitive substance is subjectedto a certain aging process, which changes the chemical properties, andthus adversely affects the properties of the created object, such as therequired biocompatibility.

It is the object of the invention described herein to create astereolithography device and a cartridge unit for such a device, whichovercome the above-described disadvantages, and to achieve a simplified,trouble-free, economical, preferably continuous, and easy-to-documentgeneration of three-dimensional objects.

This object is achieved by a stereolithography device of the typementioned at the outset, in which the cartridge unit comprises aninterior space surrounded by a casing, wherein at least a portion of thecasing is at least partially transparent to the radiation triggering thecuring process, wherein according to the invention the casing of thecartridge unit is deformable, and the interior space surrounded by thecasing has a volume that is at least partially formed by a receivingspace for the photosensitive substance. A “receiving space” shall beunderstood to mean the space in which a quantity of the photosensitivesubstance can be accommodated for at least a duration of an irradiationand curing process and is accessible to the radiation.

The above-described object is also achieved by a cartridge unit for usein a stereolithography device of the aforementioned type, wherein thecartridge unit includes an interior space surrounded by a casing,wherein the casing of the cartridge unit is deformable, and the interiorspace has a volume that is at least partially formed by a receivingspace in which a quantity of the photosensitive substance can beaccommodated for at least a duration of an irradiation and curingprocess and is accessible to the radiation triggering curing of thephotosensitive substance.

Instead of a substantially rigid cartridge of the known type, theapproach according to the invention provides a cartridge in which thecasing and the bottom are at least partially flexible and made of atleast one material. The flexible design of the casing allows thecartridge case and, if necessary, the entire cartridge body to bedeformed, for example by way of compression of the cartridge,facilitating a direct generation of the layers and adhesion of thelayers to the object support (hereinafter ‘support’), with subsequentseparation of the layers from the reference surface, while thephotosensitive substance is located within the cartridge at leastpartially during the building process. As the number of generated layersincreases, the cartridge is stretched, or is compressed (deformed) less,allowing it to restore the original shape thereof upon insertion intothe apparatus after the object to be generated has been completed, if sodesired. It shall be noted that a casing shall be understood to meanthose parts of the cartridge which delimit the interior space withrespect to the outside; optionally present, additional components thatcan be moved inside the interior space, such as a ram, a doctor blade orvalve parts, do not form part of the casing within the meaning of thepresent invention.

The invention thus also allows the photosensitive substance to be storedmore efficiently and variably within the stereolithography apparatus,and the generated layers to be gently separated from the referencesurface. Further advantages include the improved and easier control ofthe relative movement of the support of the generated layers or of thegenerated object with respect to the reference surface, and thesimplified supply and handling of photosensitive material in thestereolithography apparatus.

The cartridge may furthermore be equipped with an information carrier,via which the quantity, the type, the state and process parameters canbe inferred. Accordingly, a cartridge unit may include an informationcarrier which holds information regarding the photosensitive substance,and in particular with respect to the quantity, type and/or statethereof, and/or process parameters of a process of producing athree-dimensional object, and/or transmits this to the stereolithographydevice, for example to a control unit thereof. The information carriermay be an imprint, a bar code, an RFID chip, a magnetic strip or thelike, for example.

As mentioned above, it is advantageous when the cartridge unit can bedetachably inserted into a stereolithography device of the kinddisclosed herein. In an advantageous refinement of the invention, thecartridge unit may be detachably fastenable or fastened to the objectsupport so as to facilitate a replacement of the cartridge.

The deformable area of the casing may have a one-piece design, andpreferably be made of a flexible material, but may also have amulti-piece design if necessary. A jacket portion of the cartridge canbe composed of a film tube (such as FEP or PTFE film), while the bottomof the cartridge, in which a transparent bottom part (which in thesimplest case is at least a piece of glass), for example, is located, isa simple injection-molded part made of suitable plastic material, as isthe closing top part of the cartridge. Depending on the design, thebottom part or the top part may include the reference surface.

Furthermore, the volume of the interior space may be formedpredominantly, and preferably entirely, by the receiving space. Thereference surface is located either on the bottom (or the cover surface)of the receiving space or is defined by a suitable surface in thereceiving space, for example a membrane, an interface between two (forexample layered) liquids or at least one photosensitive substance havingdifferent states in the receiving space. The casing can, advantageously,be realized so that the surrounded interior space has a volume thatremains substantially the same during a deformation of the casing. Inmany embodiments, the deformability of the casing is realized such thata reversible compression with respect to a height of the cartridge unitis permitted. In most instances, compressive deformation is what isprimarily desired, and in these cases the deformability may thus belimited to such a reversible compression. The compression (or, oppositethereto, the stretching) may be generated, for example, by a relativemovement between a base plate of the support unit and a holding unit,which holds an end of the cartridge unit located opposite the baseplate; in general, two ends of the cartridge unit are each held in thesupport unit by a holding means, and the compression or stretching ofthe cartridge unit takes place by a relative movement of the holdingmeans with respect to one another.

In many embodiments, the casing may have a geometric shape that can befolded onto itself. In addition or as an alternative, the casing maycomprise at least one reference surface, which may have a rigid,partially flexible or completely flexible design. It is favorable whenthe reference surface formed in the casing can be moved or deformedarbitrarily in space.

The casing can, advantageously, be shaped so as to comprise a bottom, atop part, and a jacket connecting the bottom and the top part, whereinthe jacket is preferably deformable. The bottom of the casing may berealized rigid or flexible, comprising at least one layer, and/or may becomposed of multiple materials.

According to a further refinement aspect of the invention, the bottom ofthe casing and/or the jacket may comprise at least one perforatablearea, preferably weakened area(s), for creating at least one opening forsupplying or removing a photosensitive substance and/or for supplying orremoving solvent into and/or out of the interior space.

The casing of the cartridge unit according to the invention may comprisea closed bottom that is impermeable to the photosensitive substance andformed of at least one part, and side walls. However, these may bedesigned to be permeable to gases or gas mixtures. Within this meaning,it is favorable when the aforementioned jacket is designed to bepervious (permeable) to gases or gas mixtures, and in particular tooxygen or air. The bottom may also be pervious to gas in this manner.

Furthermore, the casing may include a closable opening on the upper faceand/or on the side, through which the photosensitive substance can besupplied to the interior space and removed therefrom. The casing can, inparticular, also include lateral openings or opening extensions. Thecasing may comprise sealing elements for sealing the opening. The casingmay thus comprise sealing elements on the upper opening and on thebottom side. Moreover, the opening may be closable by way of a closureelement, which preferably has a one-piece design, wherein the closureelement is preferably realized as a support for the cured layers of thephotosensitive substance.

The one-piece or multi-piece cartridge may comprise geometric,mechanical or magnetic elements, which can be joined by way of afixation to at least one element that is able to carry out a relativemovement. Furthermore, an advantageous refinement of the cartridge unitmay comprise a component that is movable in the interior space andguided in the cartridge unit by way of guides of a geometric, mechanicaland/or magnetic nature. Components movable in the casing may be doctorblades, rams, flaps serving as valves or the like, for example.

One embodiment of the invention provides that the cartridge unit maycomprise a closure part that upwardly delimits and closes the interiorspace, wherein this closure part may be replaceable and preferably havean overall rigid design. This closure part may include suitably shapedgeometric clearances, which is to say recesses or openings, in a surfacefacing the interior space of the cartridge. Clearances of this kindallow photosensitive liquid from the capsule to penetrate into theinterior space of the casing, for example. Another advantageous use ofclearances is that of improving the adhesion of the three-dimensionalobject to the surface serving as the support. The closure part maymoreover have a one-piece or multi-piece design. By way of a suitablegeometric configuration of the closure element, it is possible toprovide at least one area in which photosensitive resin or resins can bestored directly or indirectly.

Favorably, the closure element can make it possible to accommodate atleast one object filled with photosensitive resin, which is preferablyimplemented so as to be perforatable. Accordingly, it may be favorablewhen the area is configured to accommodate a receptacle comprising aphotosensitive substance, wherein preferably means for perforating thereceptacle are provided.

In addition, the closure part can comprise at least one integratedplunger, the stroke of which allows the delivery of the photosensitivesubstance to be metered. The plunger can moreover comprise units forperforating or opening a receptacle present in the closure part, and inparticular a receptacle comprising a photosensitive substance. The atleast one plunger may thus be able to damage at least one bag-shapedelement as a function of time so as to release photosensitive material.

Additionally, the plunger may comprise units for supplying a solventand/or a gas or a gas mixture, and in particular nitrogen or air.

Moreover, the cartridge unit can, advantageously, comprise anoxygen-permeable one-piece or multi-piece bottom.

So as to facilitate a detachment of the produced three-dimensionalobject, moreover a unit for generating vibrations may be provided in thedevice according to the invention.

The stereolithography device according to the invention may be providedfor the insertion of one, two or more cartridges. In particular, aplurality of cartridge units may be inserted in the device.

Further details and preferences of the invention will be apparent fromthe following description of several exemplary embodiments, which areillustrated in the accompanying drawings and are not limiting to theinvention. The drawings show the following schematically:

FIG. 1 shows a perspective view of a stereolithography device accordingto one exemplary embodiment of the invention;

FIG. 2 shows an exploded view of a cartridge unit, which can be insertedin the device of FIG. 1.

FIG. 2a shows the cartridge unit of FIG. 2 when assembled;

FIG. 3 shows a perspective view of a first embodiment of a cartridgeclosure part comprising a support and a capsule to be inserted therein;

FIG. 4 shows a longitudinal section of the closure part of FIG. 3;

FIG. 5 shows a perspective view of the closure part of FIG. 1,comprising an inserted capsule;

FIG. 6 shows a longitudinal section of the closure part of FIG. 5;

FIG. 7 shows a perspective view of a second embodiment of a closurepart;

FIG. 8 shows a longitudinal section of the closure part of FIG. 7;

FIG. 9 shows the closure part of FIGS. 7 and 8 with the stopper removed;

FIG. 10 shows an embodiment of a closure part assembled from multiplecomponents in a perspective view;

FIG. 11 shows a longitudinal section of the closure part of FIG. 10 whenassembled;

FIGS. 12 and 13 show the closure part of FIGS. 10 and 11 with theplunger actuated;

FIGS. 14a-14d show multiple variant embodiments of the casing of thecartridge unit according to the invention;

FIG. 15 shows a cartridge closure part comprising information carriersprovided thereon;

FIGS. 16a-16d illustrate, based on a sequence of four stages, thegeneration of a cured layer of the photosensitive substance, using acartridge unit according to the invention;

FIG. 17 shows a further embodiment of a cartridge system;

FIG. 18 shows another embodiment of a cartridge system; and

FIGS. 19a and 19b illustrate the replacement of a capsule of the closurepart.

FIG. 1 shows an exemplary overview of an exemplary embodiment of astereolithography apparatus 1 according to the invention for thegenerative fabrication of one or more three-dimensional objects 2 (FIGS.16a-16d ) from individual layers, which are cured from a photosensitivesubstance within a respective cartridge unit 5, 6. The photosensitivesubstance can be cured in a receiving space 4 within the cartridge unit5, 6 by way of actinic radiation. Within the scope of the presentdisclosure, “actinic radiation” shall be understood to mean (in generalelectromagnetic) radiation that is suitable for triggering the desiredcuring reaction of the photosensitive substance, and in particular lightradiation such as UV light. The photosensitive substance is generallyliquid, wherein within the scope of the present disclosure the term“liquid” refers to liquids having arbitrary viscosity, includingsuspensions and pasty substances.

One or more cartridge units 5, 6 are held by way of respectiveassociated receiving units 75, 76 and are arranged on a base plate 77.Together with the receiving units 75, 76, including the associateddrives and optionally further components (not shown in FIG. 1), the baseplate 77 forms the support unit 7 of the invention.

A controllable light source 8 is arranged beneath the base plate 77, forexample, where it can be horizontally positioned, preferably in twodirections (X and Y), by way of stepper motor-operated linear actuators81, 82. The light source 8 is configured to be movable relative to theat least one cartridge unit 5, 6 and, in this way, is positioned beneaththe cartridge unit 6 in which a building process of an object 2 is totake place. In one variant, the stereolithography apparatus may alsocomprise a rotatably mounted mirror, by way of which the light emittedby the light source 8 can be directed via further deflection mirrors tomultiple cartridge units, by deflection of the rotatably mounted mirror.

Each receiving unit 75, 76 is adjustable in terms of height with respectto the base plate 77 or the bottom of the cartridge system 5, 6, forexample by way of a stepper motor drive. The receiving unit 75, 76 isadvantageously configured to accommodate, center and hold the cartridgeunit held therein in a certain position relative to the base plate;preferably, the receiving unit 75, 76 holds the top part (closure part)of the cartridge unit and is thus able to set the height of thecartridge unit, and compress the same, by way of a movement with respectto the base plate. The support unit 7 may furthermore comprise afastening element 74, for example a body that enables form-lockedlocking, for one or each of the cartridge units 5, 6, and the bottompart of the cartridge system 5, 6 can be secured, by way of thefastening element 74, at least for the duration of the developmentprocess. A control unit 9, for example a control computer, controls themovement of the units 75, 76, 81, 82, and the sequences of themanufacturing process in the apparatus 1, including the activity of thelight source 8, and, if necessary, the control unit also receives andprocesses measuring and/or sensor signals recorded by sensors in thecartridges 5, 6.

FIG. 2 shows a cartridge system 10 in an isometric exploded view(resolved in the Z direction) as one exemplary embodiment of a cartridgeunit according to the invention, which can be inserted in thestereolithography device of FIG. 1; FIG. 2a shows the cartridge system10 when assembled. The cartridge system 10 of the shown embodimentcomprises, for example, a closure part 11, which may be identical, forexample, to the closure part described hereafter in FIGS. 3-6, a casing14 (for example, identical to the casing 141 of FIG. 14a ), and anadditional bottom 15, which is preferably at least partially transparentto actinic radiation, a locking part 16, and a cartridge reinforcementpart 17. Of course, the closure part, the casing, including the bottom,and the locking part may also be implemented in accordance with theother configurations disclosed herein, or further embodiments which aperson skilled in the art will be able to discern within the scope ofthe invention.

The locking part 16 is provided to additionally reinforce the casing 14,and this component 16 can furthermore enable referencing, centering,force-fit and/or form-locked fastening of the at least partiallyflexible cartridge system 10 in the stereolithography device 1 (FIG.16). Moreover, the locking part 16 prevents the lower cartridge areafrom bulging, deforming, bending and/or lifting off.

So as to be able to safely handle the at least partially flexiblecartridge system 10 outside and inside the stereolithography apparatus1, the cartridge system 10 may comprise a cartridge reinforcement part17, which is designed, for example, at least in a half-shell shape andadapted to the geometry of the flexible casing 14 of the cartridgesystem 10. A desired height of the cartridge system 10 is defined by wayof the cartridge reinforcement part 17. The cartridge reinforcement part17 may also be configured so as to be easily pulled from the cartridgesystem 10, which can be achieved by way of a handle or a window, forexample. The cartridge reinforcement part 17 is preferably configured tobe able to form a releasable form-locked or force-fit joint with thelocking part 16, the casing 14 and/or the closure part 11 on at leastone end, for example by clamping on the part 17 in the manner of a clip.

FIG. 3 shows an oblique view from above and the side of a firstembodiment of the closure part 11, comprising a support 102 of thegenerated layers (these are, as mentioned, built up on the bottom sideof the support) into which furthermore at least one capsule 101 can beinserted. The capsule 101 is still shown above the support 102 while notyet inserted and not perforated. At least one photosensitive substance,which may be a liquid having any arbitrary viscosity or pastyconsistency, for example, is present in the capsule 101. The capsule 101is closed by a capsule closure element 107. This closure element 107 mayalso be realized as a pressure control valve or comprise such a valve.In one variant (not shown) of the capsule 101, this may comprise apressure control valve itself.

FIG. 4 shows a sectional view (longitudinal section along the centeraxis) of the capsule 101 and of the support 102. The (unperforated)capsule 101 comprises a certain amount of the photosensitive substance 3having a starting fill level HO. The support 102 has at least oneopening 109 through which the photosensitive substance 3 exiting thecapsule 101 can reach the area beneath the support 102. In thisembodiment, the capsule 101 comprise one or more areas 104 having alower wall thickness on the bottom side 110 thereof. These weakenedareas 104 are provided for perforation by projecting profiles 105 of thesupport 102. The projections 105 are located on the bearing surface 108of the support for the capsule 101 and are designed, for example, asraised edges, which each surround an outwardly directed opening 109.When inserted in the support 102, the capsule 101 may be fixed by one ormore, preferably engaging, holding means 106, which may be realized asresilient detent hooks 106, for example. The capsule 101 can thus beinserted from above in the support 102, while being perforated at thesame time.

It goes without saying that the capsule 101 may also be fixed in thesupport 102 in another manner, for example by a bayonet catch or anadditional part that is inserted after the capsule has been inserted andfixes the latter by engagement in the support; the capsule 101 may alsocomprise a thread and be screwed into the support 102.

In one variant embodiment, the perforation may also take place by anadditional part provided on the bearing surface 108, for example a bladeor a syringe needle. In a further variant embodiment, the capsule has amulti-piece design, wherein the bottom side 110 of the capsule 101, atleast in some regions, is formed of a material that is easy toperforate, such as a film. In this case it is possible to open thecapsule 101 by perforating the film or by peeling the film off an areaof the bottom side 110 covered by the film.

In a further embodiment, which is not shown, the support 102 comprises atoothed ring or teeth configured, for example, on the lateral surfaces(in the manner of a spur gear). This allows a rotation with respect tothe bottom of the cartridge casing by a small angle α (Greek letteralpha) of a few angular degrees. As a result of this rotation, theforces required for detaching the produced object from the referencesurface can be considerably reduced.

FIG. 5 shows an oblique view of the support 102 comprising the capsule101 inserted therein, whereby the cartridge closure part 11 is formed.

FIG. 6 shows a sectional view (longitudinal section along the centeraxis) of the capsule closure part 11. Due to the perforation of thecapsule 101 by the projections 105, the photosensitive substance 3 isable to exit through the openings 109 provided in the support 102. Thefill level, as shown in FIG. 6, thus decreases from the starting filllevel HO (FIG. 4) to a level h.

FIGS. 7 and 8 show an oblique view and a sectional view (correspondingto those of FIGS. 5 and 6) of a second embodiment of the cartridgeclosure part 200, comprising a support 202, a lid 201 and a stopper 208.The support 202 contains the photosensitive substance 3. An opening 209formed in the bottom surface of the support 202 is closed by thestopper. The stopper 208 comprises a grip element or a tab and is guidedupwardly outward through an opening 207 of the lid 201; when inserted,the stopper seals the lid 201 and the support 202 to preventphotosensitive liquid 3 from exiting, wherein the sealing effect in theopenings 207, 209 may be achieved by integrated material-lockinginsertion, screwing or additional geometric profiles, as well asadditional components, such as O-rings, sealing elements or the like.The lid 201 closes the interior space of the support 202, for example byway of a force-fit and/or form-locked but sealed joint 210.

FIG. 9 shows how the photosensitive substance 3 exits the support 202the opening 209 on the bottom after the stopper 208 has been removed. Soas to facilitate the exiting of the photosensitive liquid 3, thegeometry of the opening 209 may be suitably shaped for this purpose. Inaddition, the support 202 and the lid 201 may be coated on the inside,on the surfaces that come in contact with the photosensitive substance3, with a material that ensures that as little of the photosensitivesubstance 3 as possible remains in the interior space of the support 202after emptying. This may be achieved, for example, by way of a coatingwith FEP, PTFE (Teflon) or other materials that lower the surfacetension or wetting. This variant enables easy re-filling of the cavityas well as easy cleaning. Advantageously, the stopper 208 may beconfigured such that reclosing and filling through the opening 207 ispossible.

The stopper 208 could additionally comprise filling channels (notshown), which allow the cavity to the filled through the stopper; forthis purpose, the filling openings may be realized as boreholesintroduced from above, which meet lateral borehole openings beneath thelower end of the stopper (inverted L or T shape of the channel). As analternative, the lid 201 may have a closable separate opening (notshown) suitable for filling.

FIGS. 10 and 11 show a third embodiment of the closure part 300, inwhich a ram or plunger 301 is guided inside the support 302. Theguidance of the plunger 301 preferably takes place by way of guideelements 311 and 313, for example in the form of projections orprotuberances 311, which engage in guide grooves 313 on the inside ofthe support 302, and which may thus be used for centering and guidanceand as anti-turn elements. The plunger 301 may furthermore be configuredto be removable from the support 302. This embodiment allows the closurepart 300 to be re-equipped with a bag-like receptacle 312 filled with aphotosensitive substance 3. The receptacle 312 is made at leastpartially of a perforatable material, which preferably is alsoimpenetrable to light (such as a plastic film or coated aluminum foil).On the side facing the receptacle 312, the plunger 301 compriseselements 305 formed on the inner surface, for example in the form ofneedles, teeth or blades, which allow the bag-like receptacle 312 to beperforated in a targeted manner; in addition or as an alternative, thesupport 302 may also include such perforating means itself. Theperforation may also take place in a controlled manner from the outside,for example by a needle-like body. In a further variant embodiment, thereceptacle 312 filled with photosensitive substance 3 may comprisemultiple sections, which are each filled with a photosensitive material.Due to an external, for example controlled, perforating body, theindividual section can thus be perforated in a targeted sequence.

As is also apparent from FIGS. 10 and 11, the support 302 mayfurthermore be configured so as to be able to accommodate the bag-likeobject 312 and fix and/or center the position thereof.

For this purpose, an area for accommodating the bag 312 may besurrounded by a rim or a number of tabs. The sectional view of FIG. 10shows the multi-piece closure part 300 comprising the bag-like object312 held in the support 302 in the starting position having the plungerposition h1 (measured as the distance from the upper edge of the support302).

The oblique view of FIG. 12 and the corresponding sectional view of FIG.13 show the closure part 300 in a state in which the plunger 311 is inthe end position h2 thereof. Proceeding from the starting position h1,any arbitrary position between the positions h1 and h2 of the plunger301, and ultimately the end position h2, may be achieved by theapplication of an external force F. In one variant (not shown) where theplunger comprises, for example, a helical cam or a thread having acertain pitch rotatably in the support 302, the plunger may also bemoved by applying a circumferential force (for generating a rotationalmovement).

During the movement from the starting position h1 toward the positionh2, the bag 312 is pierced by the perforating elements 305 and therebyopened. In the position h2 shown in FIG. 12, the perforated bag 312′ hasdispensed the photosensitive substance 3, which thus flows into theinterior space of the support 302 and from there exits the support 302through openings 309 provided for this purpose. In a preferredembodiment, it may be provided that the plunger 301, in cooperation withthe support 302, is configured to allow not only the perforation, butalso a compression of the receptacle 312, and thus substantiallycomplete emptying of the latter. It goes without saying that it is notessential for the plunger 301 to be a part of the closure part 300, andmoreover the plunger may, in general, have a multi-piece design, whichis to say may be divided into multiple sub-plungers, so that thesemultiple plungers can be moved independently of one another.

FIGS. 14a-14d show several examples of design variants 141, 142, 143,144 of the at least partially flexible casing according to the inventionof the cartridge unit according to the invention in schematic obliqueviews. The casing may have a single-piece design, for example, but mayalso be composed of two or more components. The basic geometry of thecasing 14, 141-144 may have any arbitrary geometric configuration,depending on the desired field of application, surrounding an interiorspace 140; for example, the casing may have a cylindrical or prismaticshape, having a circular, oval, square or rectangular outline, and theedges of the basic polygon may additionally be rounded. The casing haspreferably a cup-like basic shape, wherein it may comprise a bottom anda jacket. The jacket forms a lateral wall connecting the bottom and atop part, and the top part may form part of the casing or be formed byan additional component, such as a closure part 11, 200, 300, 400. Inparticular, preferred configurations of the casing have arotation-symmetrical design or have at least partially a box-shapedoutline.

For example, the casing 141 may comprise a jacket having smooth outerand inner surfaces, as is shown in FIG. 14a . A more complex casinggeometry is likewise possible, as is shown in FIGS. 14b and 14c . FIG.14b shows bellows-like folds of the jacket of the casing 142, allowingeasier folding of the casing 142. The casing 142 has a jacket geometrythat, in sections, has the function of a bellows. In other examples (notshown), the jacket of the casing may have a conical, trapezoidal,converging design so as to facilitate folding of the casing geometry.The casing includes at least one opening and/or suitably designedappendages and/or openings. FIG. 14c shows one example of a casing 143that is formed rotation-symmetrically in a single-piece in the base bodyand includes one or more openings via a bottom, into which an additionalcomponent 145 and/or a multi-layered bottom, which is composed ofdifferent materials, and optionally a closing transparent plate may beinserted, whereby a cavity is formed, which may be filled by way of thecomponent 145, as will be described in greater detail hereafter based onFIG. 17. As an alternative, components formed on the casing, such asinlet/outlet connectors or the like, may also be realized in one piecewith the casing. In addition, referencing FIG. 14d and the casing 144shown therein, the casing geometry may be provided with at least onerecessed and/or raised geometric profile 146 (such as a groove or a rib)in the lower area of the casing 144, by way of which an additionalbottom 15, 25 (FIGS. 2 and 17) can be fastened, which is at leastpartially transparent, for example made of Plexiglass, acrylic glass orfloat glass, to actinic radiation for curing the photosensitivesubstance and forms an additional cavity beneath the bottom of thecasing 141-144. Furthermore, this profile may provide an orientationoption and/or fastening option for the casing 144.

FIG. 15 shows an example of a cartridge closure part 500 having one ormore information carriers 502, 503 provided on the outside thereof (theupper face of the lid 501 here), in which information regarding thephotosensitive substance, and in particular with respect to thequantity, type and/or state thereof, and/or process parameters of aprocess of producing a three-dimensional object is stored. Data can betransmitted from the information carrier via suitable transmission pathsto the stereolithography device, for example the control unit 9. Theinformation carrier may be an imprint, a bar code 503, an RFID chip 502,a magnetic strip or the like, for example.

FIGS. 16a-16d represent a sequence of individual stages or phases, whichserve to illustrate the function of the cartridge unit according to theinvention (based on the example of a cartridge system 10 of FIG. 2) inone possible embodiment of a stereolithography apparatus 1 according tothe invention. For the sake of improved clarity of the illustration,only the light source 8 of the apparatus 1 and the cartridge system 10are shown in these figures, while the units for holding, positioning andpotentially deforming (compressing/stretching) the cartridge system 10are not shown. FIGS. 16a-16d illustrate the production of athree-dimensional object 2 based on a single build cycle for a layer Bnof the object 2, of which previously the layers B1 to Bn−1 have beengenerated. In the drawings of the present disclosure, thethree-dimensional object 2 is shown as a component having an invertedpyramidal shape, which is merely intended to be exemplary and shall notbe limiting; it is possible, of course, to generate a wide variety ofshapes of three-dimensional objects. The build cycle for the layer Bn,using a photosensitive substance 3, comprises the following phases:

-   Phase 1: starting position at the height A1 (FIG. 16a );-   Phase 2: lowering the support to the height A2 (FIG. 16b ), where    A2<A1;-   Phase 3: exposing or generating the layer Bn (FIG. 16c );-   Phase 4: lifting off the support (FIG. 16d ), and optionally    removing the cured layer Bn from the mold.

With this, an end position is reached, which corresponds to the startingposition (phase 1), except having a height A3>A2. The height A3 maycorrespond to or be different from the height A1 prior to the shownbuild cycle. Frequently, A3>A1 since the size of the componentincreases.

FIG. 16a represents the starting situation, in which the capsule 111 isalready perforated, from which the photosensitive substance 3 flows intothe interior space 140 of the cartridge system 10, where it fills orcovers the bottom of the casing 14, which represents the receiving spaceof the invention. In the starting position (phase 1) having the heightA1, n−1 component layers of the component 2 have already been generated,and the most recently formed layer Bn−1 is located in a position overthe bottom of the casing 14.

Thereafter, as is shown in FIG. 16b , the upper part of the cartridgesystem 10 formed by the closure part 11 is lowered, compressing thesame. The closure part 11 is advantageously lowered until the layer Bn−1makes contact (again) with the photosensitive layer 3. The layer Bn−1 isadvantageously positioned so as to be located above the referencesurface 41 by the desired layer thickness of the layer Bn to be formed.As the closure part 11 is being lowered, photosensitive liquid 3 maycontinue to exit the capsule 111, if necessary, wherein the liquidphotosensitive substance 3 still present beneath the layer Bn−1 isdisplaced until the desired layer thickness of the layer Bn is reached;in other words, the photosensitive substance 3 fills the gap between thelayer Bn−1 and the reference plane 41 formed by the bottom of the casing14 or, where necessary, a non-reactive phase 33 (see FIG. 17) of thephotosensitive substance 3. According to the invention and in keepingwith the configuration, the deformable casing 14 assumes a compressed,which is to say folded and/or bulged, state.

In phase 3, illustrated in FIG. 16c , the new component layer Bn iscured by way of actinic radiation 80, such as UV light, which is emittedby the light source 8 and focused onto the areas of the layer Bn on thereference surface 41 to be developed. In this process, analogous toconventional stereolithography methods, the structure of the layer Bn isgenerated by selection of the exposed areas of the layer Bn.

In phase 4, the layer Bn thus cured in phase 3 is lifted off the bottomof the casing 14 or the phase 33 by way of a relative movement of theclosure part 11, whereby the newly formed layer Bn is separated from thereference surface 41. The casing 14 is elastically deformed in keepingwith the magnitude of the stroke of the upward movement, and moreparticularly in general is partially relaxed.

FIG. 17 shows another embodiment of a cartridge system 20, in which thecasing 24, for example, is substantially patterned after the casing 143of FIG. 14c , in a longitudinal sectional view. A cavity 22, which isformed between the outer glass bottom 25 and the bottom side 23 of thecasing 24, is present beneath the casing 24. Due to the lateralextensions of the casing 24 or other openings (not shown) provided forthis purpose, the cavity 25 may be flooded with a fluid 19 (for example,oxygen or another gas suppressing the reaction) or other inhibitors(volume throughput VS). A non-reactive phase 33 of the photosensitivesubstance 3 forms due to the inhibitor penetrating through the permeablebottom of the casing 24 into the interior space 240 of the cartridge, inthis embodiment the surface of the non-reactive phase, instead of the(inner) bottom surface of the casing 24, forming the reference surface42. A reference surface 42 thus formed offers the advantage that thegenerated layer of the component 2 does not adhere to the bottom surfaceof the casing 24, and thus the risk of the bottom layer sticking andpossibly tearing is avoided.

In this embodiment, or other shown embodiments, it is further possibleto apply a pressure p1 to the interior space of the cartridge system,the pressure being larger or smaller than the ambient p0, which may takeplace through openings (not shown) provided for this purpose in theclosure part 21 and/or the casing 24. The interior space of thecartridge system can be flooded with a specific inert gas (such asnitrogen), for example, which prevents oxygen inhibition of alreadyformed layers, and thus positively influences the mechanical strength ofthe layers and the surface quality thereof.

FIG. 18 illustrates a further possible embodiment of the casing 34(which is designed corresponding to the casing variant 144 of FIG. 14d )and a composition of the cartridge system 30. In this variantembodiment, the casing 34 comprises a discontinuous bottom 344 (which isto say not solid), which thus includes an opening 18 (or a plurality ofsuch openings). This opening is closed by way of an inserted plate- orleaf-shaped component or component combination 35. This component 35 mayhave a multi-piece design, where necessary, and ensures a closedinterior space 340 of the cartridge system 30 and the upper face thereofforms the reference surface. The component 35 may have a sandwichdesign, for example, which is at least partially transparent to theactinic radiation used for curing the photosensitive substance 3 and isat least partially permeable to gases; for example, an elastic film 31(such as FEP film, Teflon film) may be formed on a support part 32 madeof a material such as microporous glass, which exhibits particularlygood permeability to the gas or gas mixture used for forming anon-reactive phase 33 (see above with respect to FIG. 17).

FIG. 18 furthermore shows another aspect of implementing the casing,based on the variant of the casing 144 of FIG. 14d , wherein the jacketof the casing 34 is formed of multiple segments (341, 342, 343), and theindividual segments may have differing material properties. This allowsa cartridge casing to be formed which comprises, for example, areashaving differing flexibility and/or differing optical properties. Asegmentation of the jacket can, of course, also be provided with any ofthe other embodiments shown herein.

A further aspect of the invention is shown in FIGS. 19a and 19b , basedon sectional views of a cartridge system 40 according to the invention,namely the replacement of a capsule so as to switch between differentprocessing types, such as from a layer build process to a cleaningprocess. FIG. 19a shows the cartridge system 40, in which an object or acomponent 2 was built by way of the photosensitive substance 3, inaccordance with the sequences described above; the photosensitivesubstance 3 is provided by a capsule 401, which is inserted into thesupport 402 of the cartridge system 40. By removing the capsule 401 andreplacing the same by inserting a new capsule 404, which is compatiblewith the closure part 400 of this exemplary embodiment, it is possibleto supply a different substance instead of the photosensitive substance3. For example, the capsule 404 can be filled with a solvent 43, such asisopropanol. As a result of the insertion of the capsule 404 andperforation of the outer casing of the capsule 404 in the course of theinsertion into the interior space of the support 402 of the closure part400, the solvent 43 is released and can reach the interior space 440 ofthe cartridge system 40 through the openings of the closure part 400. Asis shown in FIG. 19b , the solvent 43 partially or completely fills theinterior space of the cartridge system 40, thereby allowing thecomponent 2 to be cleaned, and in particular photosensitive substance 3still adhering to the component 2 to be removed and/or residualphotosensitive substance 3 present in the interior space, which has notyet or only partially cured, to be dissolved. Due to the photosensitivesubstance 3 dissolving in the solvent 43, a solution or mixture 13 isformed in the interior space of the cartridge. This may now be drainedvia openings in the closure part 400 by tilting or inverting thecartridge 40. For example, the mixture 13 may flow out of the interiorspace 440 of the cartridge system 40 through the openings in the support402 during removal of the capsule closure part 403. If desired, theliquid may then be replaced with new solvent. The cartridge unit may beconfigured so that a dissolution of the photosensitive substance 3 canbe promoted by vibration, centrifuging, shaking, increasing thetemperature or other suitable measures.

Similarly to what is shown in FIGS. 19a and 19b , it is also possible toswitch between different types of photosensitive substances, for examplewhen the object 2 is to be composed of different materials, and/ordifferent liquids are desired for cleaning and/or post-curing of theobject 2.

A replacement or a continuous exchange of the liquids may also beachieved by supplying a new (in general, a liquid or suspension-like)substance via a first opening in the support 402 or the casing 44, whichdisplaces the substance in the interior space; the substance thusdisplaced can drain via a second opening. Suitable pumps may be providedin the supply line of the first opening and/or the drain line of thesecond opening.

The above embodiments of the cartridge unit or stereolithography deviceaccording to the invention can, moreover, comprise the following aspectsand refinements, depending on the application:

The cartridge unit can directly or indirectly comprise thephotosensitive substance and is realized in one piece or assembled frommultiple components. The casing may have a three-dimensional shape andis preferably realized in one piece, wherein the deformable portion ofthe casing, which is preferably a laterally peripheral jacket, may bemade of a flexible or foldable material. The bottom of the casing may beat least partially translucent and gas-permeable, and may be made of amaterial suitable for this purpose, for example silicone or amulti-layer material composite comprising silicone, glass and/or plasticlayers, for example having a sandwich-like composition. Thestereolithography device is provided with a light source, which ispreferably movable and displaceable in a controlled manner, forselectively exposing the photosensitive substance, and at least oneobject support (also referred to as a support holder or support forshort). The object support is arranged inside or outside the cartridgeunit and, if necessary, may be movable relative to the bottom of thecartridge.

In another variant, the jacket portion of the cartridge may be made of afilm tube (such as FEP or PTFE film), while the bottom of the cartridgeand the closing top part of the cartridge are simple injection-moldedparts made of suitable plastic material and/or suitable multi-layercomposite materials. The costs of this variant embodiment areconsiderably lower than those of the silicone injection moldingconfiguration, and the film would additionally be thinner and easier todeform.

The photosensitive material may be present in the cartridge in areceiving space (or multiple receiving spaces) formed therein, to whichit has been added, for example, before the cartridge was inserted intothe apparatus, or it may be supplied in one or more receptacles, whichare inserted in the cartridge, for example in a receiving space withinthe cartridge body, the support (object support) or the casing itself,provided for this purpose. The support, which may also serve as theclosure part and may have a single-piece design or be formed of multipleparts, may include at least one geometric cut-out in which thephotosensitive substance or a receptacle therefor can be accommodated.This cut-out may additionally comprise a specially shaped surface orstructures, or a component having a specially shaped surface orstructures can be inserted therein, wherein this surface or thesestructures can cause a perforating effect on another body. The supportor the cut-out may thus accommodate and/or store at least onephotosensitive substance, containing the same directly or indirectly ina receptacle.

This eliminates complicated replenishing and dosing units andcomplicated cleaning of the support. A particular advantage is yieldedwith the cartridge system (cartridge unit) according to the inventiondue to the simple and contamination-free insertion and removal into andout of the stereolithography apparatus. It is possible to switchquickly, and without long cleaning and setup times, between differentcartridges, which comprise different photosensitive substances, forexample. It is thus also possible, for example, to activate a secondcartridge in an apparatus during a build process that has alreadystarted, so as to increase the utilization of the apparatus. Moreover,since the substance quantity within the cartridge is known, it ispossible to generate only a precisely defined number or a preciselydefined object volume, depending on the requirement. It is thuspossible, by way of the cartridge system according to the invention, toprecisely define the life of the photosensitive substance, andconsequently it is also possible to determine the object and materialproperties to be expected in the cured state, such as a desiredbiocompatibility. The cartridge system according to the invention can beeasily removed from the apparatus, including the formed object on thesupport, and thereafter a post-processing system (for example, forcleaning and/or post-exposure) can be introduced, which is configured toaccommodate the cartridge system and, possibly, introduce and/or removecleaning agent, for example a solvent such as isopropanol, throughopenings or by perforating the cartridge itself in suitable locations.

Moreover, a specific atmosphere may be initiated in parts of thecartridge via the same and/or other suitable openings provided for thispurpose. In this way, the now cleaned or partially cleaned cartridge,comprising the cleaned object on the support located therein, may serveas a cavity that is filled with inert gas. The casing is preferably atleast partially translucent, and particularly preferably the casing andthe bottom of the cartridge are translucent, and made of the sameflexible material, such as silicone. Many advantageous embodiments arecharacterized in that the casing and the bottom of the cartridge arerealized in one piece made from a translucent, flexible and chemicallystable as well as oxygen-permeable material, such as silicone, andparticularly preferably a liquid silicone rubber (LSR) material, whereinthe closure part and potential other parts or portions thereof, such asthe support and/or the plunger or plungers and/or the capsule orcapsules filled with photosensitive material, may be made of anon-translucent material. The support may comprise at least onegeometric cut-out, via which the photosensitive substance can passthrough the plunger, or past the same, into the area of cartridgeprovided for exposure, or to the cartridge bottom, based on gravity orby way of pressure that is applied by the support.

Since the invention makes a separate storage option for thephotosensitive substance in the closure part or in a cavity formed inthe closure part possible, the design can preclude swelling or diffusionof the substance into more sensitive areas of the cartridge. It isadvantageous when the photosensitive substance is additionally enclosedin a receptacle, for example a bag-like receptacle, or a specificallyshaped receptacle body, which is preferably located in the support orallows to be inserted therein. The closure part, or more preciselyportions thereof, such as the rear side of the support, is configured,based on the design and/or based on the surface properties, to perforatea receptacle (for example a bag) comprising the photosensitive substanceso as to thereby release the photosensitive substance. In anotheradvantageous embodiment, a disposable capsule filled with aphotosensitive substance can be pierced by a specially shaped portion ofthe support, whereby the photosensitive substance is released.

The cartridge system may be usable once or be designed to be usedmultiple times. It may thus be configured as a disposable system or berefillable.

Depending on the configuration, the cartridge unit according to theinvention enables a simpler, more precise measurement of the gasmixture, lower amounts of gas, a more precise design of the gas volumeflow since the amount of the photosensitive substance is preciselyknown, for example as a result of the capsule filling, safer and simplerhandling of the photosensitive substance, a safe and more stableprocess, and prevention of contamination. Furthermore, the presentinvention dispenses with a completely or partially gas-tight design ofthe apparatus since the gas can be limited to the cartridge.

In a further favorable configuration, the casing of the cartridgecomprises a double bottom, which may have a single-piece or multi-piecedesign. The portion closing the casing (for example downwardly), whichforms the reference plane, and in the simplest case also the bottom ofthe cartridge system, may be composed of a non-flexible or onlypartially flexible, multi-layer bottom, which is transparent to actinicradiation and permeable to specific gases or gas mixtures. A supportingelement, which is likewise permeable to gases, may be present beneaththe cartridge casing.

The connection between the aforementioned bottom surface and the casingmay be configured to be gas-tight. The casing itself may comprisesealing elements, such as special beads. In another advantageous variantembodiment, the casing of the cartridge may be configured such that adouble bottom is formed with respect to the casing only after insertioninto the apparatus according to the invention, wherein the transitionalpart is configured completely or partially gas-tight. The cartridge unititself may moreover also be stored in a gas-tight cladding in theapparatus, such as in a pipe. This creates a geometrically arbitrarilyshaped cavity which, depending on the requirements and possibilities ofthe application, may comprise at least one access opening and/or atleast one discharge opening, via which a specific gas or a gas mixturecan be introduced, or was already introduced. The first bottom of thecasing of the cartridge system, which is made of at least one materialthat is partially or entirely permeable to the gas or the gas mixture,is preferably made of silicone or a material combination comprisingsilicone and/or a permeable material, such as PTFE or glass. The closingportion of the casing can, as was already described, likewise be made ofa microporous glass permeable to gas. In this way, a gas or gas mixturecan be supplied to the inner volume of the cartridge and/or bedischarged therefrom directly or indirectly from beneath. In a furtherembodiment, the cartridge system comprises a sensor or sensing probe,which is able to measure the diffusion of the gas or of the gas mixturein a time-resolved manner so as to thereby control the volume flow ofthe gas or of portions of a gas mixture over the duration of theprocess. The sensor may already be present in the cartridge, such as inthe support. For example, the sensor may be introduced during insertionof the cartridge system and, where necessary, be positioned by way of alocking or centering procedure of the cartridge through a special,previously sealed opening or by perforation of the cartridge. It isfavorable when the position of the sensor is selected such that thesensor does not make contact with the photosensitive resin, or when thesensor is configured such that a contamination does not result in adistortion of the measurement and in increased measuring uncertainty.The measuring of the atmosphere within the cartridge may take place byway of direct or indirect methods. A particularly advantageous measuringmethod is one in which the sensor or sensing probe is arranged outsidethe cartridge or the casing, and enables a measurement of thecomposition or of the gas concentration within the cartridge; for thispurpose, the permeability of the casing itself may be utilized, so as tobe able to infer the gas concentration in specific areas.

In further embodiments of the invention, different gases or gas mixturesmay be supplied within the cartridge. For example, oxygen may besupplied from beneath through the bottom of the cartridge in a higherconcentration than in the normal atmosphere, and nitrogen may besupplied from above through the support, so as to deliberately influencethe properties of the photosensitive resin or of the processing thereof,and ultimately the final properties of the body that is created.

A person skilled in the art will, of course, be able to readily make avariety of modifications and additions to the embodiments of theinvention disclosed herein, to the extent these are within the scope ofprotection of the claims below.

The invention claimed is:
 1. A stereolithography device (1) for producing a three-dimensional object (2) by way of layered or continuous curing of a photosensitive substance (3) under the action of specific radiation triggering the curing process, the device comprising: a support unit (7); a radiation source (8) for generating the radiation (80) triggering the curing process; and at least one cartridge unit (5, 6) which is configured to be positioned on the support unit and removed therefrom and which includes (1) an interior space surrounded by a casing (14), at least a portion of the casing being transparent to the radiation triggering the curing process, and (ii) a closure element which is configured to close the interior space during an irradiation and curing process, wherein the casing (14, 141, 142, 143, 144, 24, 34, 44) of the at least one cartridge unit (5, 6, 10, 20, 30, 40) is deformable, and the interior space (140, 240, 340, 440) surrounded by the casing has a volume that is at least partially formed by a receiving space (4) configured to receive, and make accessible to said radiation, a quantity of the photosensitive substance (3) for at least a duration of the irradiation and curing process.
 2. The device according to claim 1, wherein the cartridge unit (5, 6) is configured to be fixed detachably to the support unit (7).
 3. The device according to claim 1, wherein a deformable area of the casing has a one-piece design, and is made of a flexible material.
 4. The device according to claim 1, wherein the volume of the interior space (140) is formed predominantly by the receiving space (4).
 5. The device according to claim 1, wherein the interior space (140) surrounded by the casing has a volume that remains substantially the same during a deformation of the casing.
 6. The device according to claim 1, wherein the casing is deformable in a way that permits a reversible compression with respect to a height of the cartridge unit.
 7. The device according to claim 1, wherein the casing (14, 24, 34, 141, 142, 143, 144) has a geometric shape which is foldable onto itself and comprises at least one reference surface (41, 42).
 8. The device according to claim 1, wherein the casing comprises a bottom, a top part, and a jacket connecting the bottom and the top part, wherein the jacket is deformable.
 9. The device according to claim 8, wherein the bottom of the casing and/or the jacket comprise least one perforatable area for forming at least one opening for supplying or removing a photosensitive substance and/or for supplying or removing solvent into and/or out of the interior space.
 10. The device according to claim 8, wherein the jacket and/or the bottom are configured to be permeable to oxygen, air, and other gases or gas mixtures (19).
 11. The device according to claim 8, wherein the casing includes a closable opening on the upper face and/or on the side, through which the photosensitive substance can be supplied to the interior space and removed therefrom.
 12. The device according to claim 11, wherein the casing comprises sealing elements for sealing the opening.
 13. The device according to claim 11, wherein the closure element (11, 21, 100, 200, 300, 400, 500) has a one-piece design, wherein the closure element is realized as a support for the cured layers of the photosensitive substance.
 14. The device according to claim 1, wherein the cartridge unit comprises a component that is movable in the interior space and guided in the cartridge unit by way of guides of a geometric, mechanical and/or magnetic nature.
 15. The device according to claim 1, wherein the closure element (100, 200, 300, 400, 500, 11, 21) upwardly delimits and closes the interior space, wherein the closure element is replaceable and has an overall rigid design.
 16. The device according to claim 15, wherein the closure element comprises geometric clearances formed in a surface facing the interior space.
 17. The device according to claim 15 wherein the closure element has a multi-piece design and comprises at least one area (101) configured to store one or more photosensitive substances.
 18. The device according to claim 17, wherein the area is configured to accept a receptacle (101, 312, 401, 404) comprising a photosensitive substance, the device further comprising elements (105, 305) for perforating the receptacle.
 19. The device according to claim 15, wherein the closure element comprises at least one integrated plunger (301), the plunger having a stroke enabling the delivery of the photosensitive substance to be metered.
 20. The device according to claim 19, wherein the plunger (301) comprises units (305) for perforating or opening a receptacle (312) present in the closure element, and wherein the receptacle comprises a photosensitive substance.
 21. The device according to claim 19, wherein the plunger comprises units for supplying a solvent and/or nitrogen, air, or another gas or gas mixture.
 22. The device according to claim 1, wherein the cartridge unit comprises an oxygen-permeable bottom that has at least a one-piece design.
 23. The device according to claim 1, further comprising a unit for generating vibrations, which facilitate a detachment of the produced three-dimensional object.
 24. The device according to claim 1, wherein a plurality of cartridge units (5, 6) can be inserted into the device. 